Refrigerating apparatus



' Nov. l2, 1929. J. M. ETIENNE REFRIGERATING APPARATUS Filed Dec. 2o. 192s w E E INVENTOR Jose-.PH METIENNE reame Nov. i2, 192e JOSEPH '.M. ETIENNE, OF SAN FRANCISCO, CALIFOB-NIA REFRIGERATING 'APPARATS Application sled December zo, 192e. sera No. 156,015.

This invention relates particularly to an automatically operated refrigerating apparatus. y An object o f the invention'is to provide a refrigerating apparatus capable of maintaining a predetermined temperature i'n one or more independent compartments or cooling rooms.-

A further object of the invention is to provide a refrigerating apparatus having a plurality of independent compartments to be cooled, each compartment being provided with a thermostat therein to cause the temperature in each compartment to be main- 15. tained at a selected temperature and having the thermostats in all the compartments related so that a 'lowering of the temperature in all of the compartments will cause the apparatus to stop functioning until such time 2c as the temperature in one or more of the' compartments rises above the selected low temperature ,when the apparatus automatically resumes operation.

A further object of the in/vention relatesl to. a refrigerating apparatus of a conven# tional -character, in which a predetermined supply of refrigerant to the rooms to be cooled is controlled automatically by temperature responsive devices in each 'of the roo` s, the said refrigerant being circulated thr ugh the cooling coils by a compres :or

which may be started and stopped in ope va tion by said temperature responsive devices, provision being made in my-apparatus to supply ammonia gas or refrigerant to the compressor when the volume of refrigerant being circulated through the rooms to be cooled is less than the'predetermined supply.

A still further object of the invention isl 40 to provide, in com'bination with the refrigerant compressor of a refrigerating apparatus that is adapted to have 'a predetermined pressure of refrigerant therein, a'conduit to supply refrigerant to the compressor automatically and at such times when the pressure of the refrigerant in the apparatus drops below or is le'ss than the predetermined pressure.

In this specification and the annexed drawings, the invention is illustrated inthe form considered to be the best, lbut it is to be understood that the invention is not limited to such form, because it may be em bodied in other forms, and it is also to be understood that in and by the claims following the description, it is desired to cover the invention in whatsoever form it may be embodied.

Other ,objects of the invention are to provide a refrigerating apparatus that will lbe superior in point of simplicity, inexpensiveness of construction, positiveness of opercoA aton and facility and convenience in use l the drawings comprises a plurality of con1' partments or cooling rooms 1 and'2,.each having a coil of pipes 3 and 4, respect1vely,

arranged therein. Each of the coils vin the compartments to be cooled are expansion coils in which the liquid refrigerant under pressure may expand and perform the: cooling functions expected of it. have shown but two compartments to be cooled, I wish it to be understood that my in.-

vention may be applied equally well to an apparatus including a greater `number of com- A partments to be cooled.

. 'The refrigerantused in my system, preferably anhydrous ammonia, is stored in a receiver 5 in liquid-form, from which it.A is passed, through a conduit 6, into an. automatic expansion valve 7. The refrigerant held in the receiver 5 is under pressure and the expansion valve causes the pressure of the refrigerant to be reduced at the time it is discharged into a distributing drum 8. The

Although Il low pressure refrigerant is distributed from `the drum 8 through a set hand valve 9 to a-conduit 10 which communicates through a motor operated or magnetic Ivalve 11 with the expansion coil 3 in the compartment 1. A

-similar set hand valve 12 on the drum 8 is connected by a conduit 13 to a motor operated ory magneticv valve 14 on the expansion coil 4 inthe 'compartment 2. The refrigerant admitted into the expansion coils 3 and 4 is discharged therefrom into a return conduit 15 or suction line that is connected to arefrigerant compressor 16. The compressor 16 draws the expanded refrigerant fromthe suction line 15, compresses the refrigerant and dischargesit through a discharge line 17 into a condenser 18. From the condenser 18 the compressed refrigerant-passes through a conduit 1 9, in aliquid form, back into the receiver 5.' The system and apparatus thus far described is more or less conventional, to many of the refrigerating'apparatuses now in use. y i l The automatic expansion valve 7, as shown in detail in Fig. 3, is a standard type of automatic valve. In this valve the refrigerant is admittedthrough an inlet port 25, thenit passes through a valve 24, controlled by a diaphragm' 22. The spring tension of the diaphragm is regulated .by a set screw 23.l From the valve 24 the refrigerant passes into a chamber 21, and under reduced pressure is*v discharged out of the port 21. The expansion valve 7 can beregulatedto reduce the pressure of the refrigerant to any desired pressure. 1

The condenser 18, receiver 5 and other'operative connections leading from the compresser 16fto the expandin valve 7 constitute the high pressure s'1de of t e refrigerant circuit. The coils 3' and their operative connections leading to the compressor intakeconstitute the low pressure side of the refrigerant circuit.

Y Each 'of the motor operated or magnetic valves' 11 and 14 consist lof a motor 26 having Van armature shaft 27 thereon that extends within a.v casing 30 having the inlet ports 31 and` 32, respectively, formed therein. The motor" shaft 27 is provided with an eccentric 33 thereon. The eccentric .33 is adapted to displace a valve 34,`mounted within the casing 30 from its valve seat 35, the valve 34 being vieldably pressed by a spring 36; against the valve seat, thus tending to hold said valve closed. The valve 34 is thus openedor closed bythe eccentric on the motor shaft, depend- Y ing lupon the position of the temperature re-v g sponjsive devices, to be hereinafter described.

' In the compartment 1, I have provided a thermostat or other equivalent temperature v responsive device 38 and a similar thermostat 39 in Vthe compartment 2. The thermostats are shown lin enlarged form in Fig.4 2.

- The thermostats are of a conventional type each bulb to run from the h1gh end to the low end thereof. The bulb 41 is provided with a contact 43 therein connected bya wire -44 to a terminal 45 on one of the motor operated or magneticyalves 11 and 14. The

connections between each thermostat and each magnetic or motor valve being the same, only one of the connections will be described, as it will apply equallywell to the other. The opposite end of the bulb 41 has a contact 46 therein connected by a wire 47 to a terminal 48 on one of the motor operated valves 11 or 14. A. dual contact 49 is arranged adjacent each`of the opposite ends of the bulb 41 and is connected by a wire 50 to a terminal 51 on one of the motor operated valves 11 or 14.

-Electrical energyis supplied to the wire 50 and through it carried to the dual contact 49.

AWhen the bulb 41 is in the position shown in Fig. 2, said bulb is so tippedthat the mercury 51 therein will connect one of the contacts 49 with the .contactl 46 to pass the electrical energy through the wire 49 to the motor operated valve to cause said motor to rotate in' a forward direction. When the bulb'41 is tipped into the opposite position the mercur 51 will connect the other contact 49wi t the contact 43, and through it the electrical energy will be carried'to the motor to cause said motor to rotate in' a reverse direction. Asheretofore described the tipping ofthe `bulb 41 is actuated'v and controlled by the stack of diaphragms 40 in each thermostat.

Thus, the supply of refrigerant from the low pressure drum8 into the respective expansion coils 3 and 4, -is passed through the motor opverated or magnetic valves 11 and 14 and said valves are inturn automatically operated by the temperature responsive devices 38 and 39 in each compartment to be cooled.

Each thermostat is also provided with va y I second bulb 42 having a pair of contacts 52 and 53 at one end thereof, which are adapted to be connected by mercury 54 when the bulb 142 is tipped into the position shown in Fig.

2." The contact 52 is connected by a wire 55 to a line 56 that leads to one side of thelmotor 57 for .operating th'ecompressor 16. ,The

, other contact 53 is connected by a wire 58 toaline 5 9 that is `also connected to the compressormotor 57. Each of the thermostats' 38 and 39 are connected in parallel to the lines that supply electrical energy to the motor. Thus the bulb 42 in one thermostat may tip so astodisconnect one thermostat from the compressor motor, but the compressor motor will continue to operate so long as the contact l connecting the source of electrical energ to the said motor is not broken by the other t ermostat. If the temperature in one of the compartments v drops below a selected low minimum temperature, the thermostat in that compartment will tip causing the motor operated or magnetic valve to close, preventing more refrigerant from entering the expansion coil. The same action of the thermostat will also break the connection to the compressor'motor, but the thermostats in all compartments being connected in parallel, the compressor motor will not stop until all thermostats have tipped into the inoperative position'. As the thermostat in each compartment ca uses the valves controlling the refrigerant supply to thel expansion coils to be cut olf, the refrigerant compressorl has less work to do, and being of afixed capacity, will, in a short time, possibly create a Vacuum in the suction line connected to the expansion coils. Itis an object vof my invention to keep the compressor 16 in operation just as longvas any one of the expansion coils in any one of the compartments is receiving refrigerant from the source of supply. I eliminate continued starting and stopping of the compres-v sor, as the source of refrigerant supply is connected or disconnected to each cooling compartment. The connections that I have made, heretofore, are such that so' long as one cooling compartment remains in operation, the compressor will also remain in operation, to circulate refrigerant therethrough. When only one of the expansion coils is drawing refrigerant from the source of supply, the capacity of the compressor issuch that it will in a short time create a pressure in the'said expansion coil below the predetermined pressure. In order to keep the pressure of the refrigerantin the coil or coils above the predetermined pressure and to overcome the possible umping of a vacuum in the suction line, .connect a. conduit 60 to the top side of the condenser 18 or to any other source ofrefrigerant supply, and to the'suction line 15. A regulating valve 61 is provided in the bypass line 60, to regulate the amount of refrigerant to be by-passed from the condenser 18 or other source of supply back into the suction line. The .valve'l can be adjusted to maintain any desired pressure on the Suction line to prevent the system from operating with a vacuum or a pressure lower than the predetermined pressure in the suction line.

The by-pass conduit 60 supplies refrigerant 0r gas to the suction line leading to the compressor,` giving the compressor work to do (and prolonging theperiod-of operation of the compressorfwhich would otherwisel be materially shortened if the compressor were allowed to stop operating when receiving a sub-normal supply of refrigerant from anyl single expansion1 vcoil remaining in operation), and keeping a partial supply of refrigerant in the expansion coils and suction line. Just as soon as any last operating expansion v coil has its supply ofA refrigerant cut oil' from the source ofA supply, then the compressor will be stopped from'operating andthe entire system willremain at astandstill. The compressorrwill only be stopped fr'om operatingv when the temperature in all of`the compartments drops below a. selected minimum low temperature. When the temperature in any single compartment rises above the low minimum, the compressor is againv started in op'- eration land the entire system made operative..

In order to prevent hot7 gas or refrigerant flowing from the condenser and back through the by-pass 60 and suction line 15 to the cooling coils 3 and 4 to heat or defrost said coils, I provide check valves and 71, respectively, 0n the coils 3 and 4. The check valves permit refrigerant to go toward the compressor but not from the compressor into the coils.

Having thus described this invention, what Patent is:

1. A refrigerating apparatus comprised of a plurality of compartments to be cooled; a coil in each compartment; a refrigerant compressor; a high pressure refrigerant line leading from the compressor to each compartment coil to circulate refrigerant thereto; a low pressure refrigerant lincleading from each compartment coil to the compressor to return refrigerant thereto; a tcmperature responsive device in each compartment; means operable by each ten'iperature I now claim and desire to secureby Letters responsive device tev automatically regulate l and intake sides of the compressor; and

means in saidby-pass responsive to thepressure on the discharge side of the compressory for permitting the passage of refrigerant"y from the discharge side of the compressor to the ,intake side thereof, to maintain the volume of refrigerant to the compressor substantially constant.

2. A refrigerating apparat-us comprising a compressor, condenser, evaporator and expansion valve connected to form a closed sysintake sides of the compressor, and means inl Vsaid b ass res onsive to the ressure on y l? a the lovv side of the system for permitting the passage of gas from th'e discharge side of the compressor to the intake side thereof to maintain the volume of gas to the compressor substantially constant.

3. A. refrigerating apparatus comprising a compressor; a condenser; a plurality of evaporator coils; and an expansion valve connected to form a closed system, the evaporator coils being disposed in a plurality Ofcompartments to be cooled; a temperature responsive device in cach compartment to automatically disconnect the refrigerant supply `from the respective evaporator coils; a b

pass connecting the discharge and inta ie sldes of the compressor; and means in said by-pass responsive to the pressure on the low side of the system for permitting the passage of refrigerant from the discharge "side of the compressor to the intake side thereof, to maintain the volume of refrigerant to the compressorsubstantially 'constant'.

4. A refrigerating apparatus comprising a compressor; a condenser la plurality of evaporator coils; and an expansion valve con'- nected to form a closed system, the evaporator coils being disposed in different compartvments to'be cooled; an electrically operated valve between each evaporator coil and the expansion valve; a thermostat in each com partment connected to a source of electricity for automatically actuating the corresponding electrically operated valve in accordance With the temperature in the compartment; -a by-pass connecting thev discharge and intake sides of the' compressor; and means in "said by-pass responsive to the pressure on the low side' of the system for permittingv4 the passage of refrigerant from the discharge side of the compressor to the intake side thereof,

to maintain the volume 'of refrigerant to the i compressor substantially constant.

5. .A refrgerating apparatus comprising a. compressor; a condenser; a plurality of evaporatorrcoils, and an expanslon valveconnected to form a closed system; the -evaporator coils being disposed in a plurality ofcompartments to *bev cooled; a temperature responsive device in each compartment to automatically disconnect the refrigerant supply from the respective evaporator coils; a bypass connecting the discharge and intake. sides of the compressor; means in said by-v pass responsive to' the pressure on the low side ofthe system for permitting the passage of refrigerant from the discharge side'of the compressor to the intake side thereof, to

v,maintain the volume of refrigerant to the compressor substantially constant; and

when the temperature in allthe compartments reaches a selected degree.

6. A `refrigerating apparatus comprising a compressor; a condenser, a plurality .of evaporator coils, and an expansion valve connected to form a closedgsystem, the evaporator coils being disposed in different .compartments to be cooled; an electrically operated valve between each evaporatorcoil A'and the expansion valve; a thermostat in each compartment connected to a source of electricity for automatically actuating the corresponding 'electrically operated valve in accordance with the temperaturein the compartment; a by-pass connecting the discharge and intake sides of the compressor; means in said bypass responsive to the pressure on the low side of the system for permitting the passage of refrigerant from the discharge side of the compressor to the intake side thereof, to maintain the volume of refrigerant to the compressor substantially constant; and means operable by each temperature responsive device to render the compressor inactive when the temperature in all the compartments reaches a selected degree.

7. A refrigerating apparatus comprising an electric motor `driven compressor, a'condenser connected to the discharge side of the the condenser, a plurality of evaporator coils connected-to the expansion valve, and to the intake side of the compressori; an electrically actuatedl valve connected between the expansion valve and each coil for controllingl thel supply -of refrigerant to the respective coil; temperature res onsive means 1n the compartments coole by sald colls, and connected .to a source of electricity and to said electrically actuated v'alves for disconnecting the supply of refrigerant to a coil when the temperature in the compartment around the coil reached a certain low temperature; each of' connected to the said electric motor as `to renderisaid motor inactive when the tempera-` ture in all Athe compartments falls below7 a selected degree; a by-pass connecting-the in-v take and discharge sides of the compressor; and means in said'by-passres onsive to the pressure on the intake side of t e compressor :for permitting pasasge of refrigerant from the discharge side of the compressor to the :said temperature responsive means being so intake 'side thereof, to maintain the'volume of refrigerant to constant. i In testimon my hand. at

JosEPH M.- l ETIENNE., j

means operable by each temperature responsive device to render the compressor inactive the compressor substantially 126 whereof, have hereuntol set,` l an Francisco, California, this 4 30th day of October, 1926. Y 

